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Related: Editorials & Other Articles, Issue Forums, Alliance Forums, Region ForumsMarijuana’s Long Term Effects On The Brain Finally Revealed!
University of Texas just published their research into the long-term effects of marijuanaWith a drug war against marijuana still raging in more countries than not, the question of how long-term marijuana use effects the human brain is a pivotal question in its legalization. Although alcohol remains legal despite heaps of evidence to the dangers of long-term use, the fight to make marijuana available both with regard to its medical properties (especially in selectively killing cancer cells) and non-medical uses has frequently hinged on the various claims made about marijuanas effects on the recreational user.
Luckily, the debate can finally move out from the realm of opinion into scientific evidence as researchers from the University of Texas just published their research into the long-term effects of marijuana use on the brain in PNAS (Proceedings of the National Academy of Sciences).
The researcher helped dispel the dying myth that marijuana use lowers IQ, and actually provides more evidence to marijuanas potential role in fighting Alzheimers. The research revealed that earlier onset of regular marijuana use leads to greater structural and functional connectivity in the brain. The most significant increases in connectivity appear as an individual begins using marijuana, with results showing that the severity of use is directly correlated to greater connectivity.
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panader0
(25,816 posts)LiberalArkie
(15,728 posts)now so it should really put me at ease.
rhett o rick
(55,981 posts)Clinton still sees the need to control the poor people with drug laws and enrichen the for-profit prisons.
Katashi_itto
(10,175 posts)Chicago1980
(1,968 posts)Smh...
Yeah, she's really trying to control the poor people.
rhett o rick
(55,981 posts)The 1% can snort all the coke they want but the persecution of weed smokers is class related. Clinton wants to keep marijuana illegal to fill the private prisons that will give her a good kick back.
LiberalArkie
(15,728 posts)Chicago1980
(1,968 posts)She also said that their needs to be more research on it for medicinal reasons.
She's been talking about prison reform.
Just because she's not for full legalization now, doesn't mean she can't or won't be in the future.
BeanMusical
(4,389 posts)"She also said"
"She's been talking"
She talks a lot but won't walk the walk.
LanternWaste
(37,748 posts)"She talks a lot but won't walk the walk..."
I'd offer an unsupported allegation too if my biases depended on doing as such.
rhett o rick
(55,981 posts)to boot. It's been researched for years. It gives relief to people in pain, yet she would deny that.
She's been talking about prison reform. That's total rhetoric. How long will she "talk about it" before she makes a stand?
"Just because she's not for full legalization now, doesn't mean she can't or won't be in the future." True, but it's time now and how long would you wait before you realized you'd been had?
bvar22
(39,909 posts)They make money on occupancy per day, so to maximize profits, they try to stay full.
The Marijuana Laws currently do that.
I don't see Hillary biting the hand that feeds her.
LiberalArkie
(15,728 posts)music
Chicago1980
(1,968 posts)Kokonoe
(2,485 posts)And people say she followed Bernie.
I say, we got work to do.
WhaTHellsgoingonhere
(5,252 posts)edgineered
(2,101 posts)Back then it seemed like every other shop was a head shop. We would buy all sorts of pipes and various papers, sometimes having to roll up joints of homegrown as big around as a dime. Today's bud isn't anything like that, you won't need as much as you think.
Unknown Beatle
(2,672 posts)One to two hits and you're stoned for four to five hours.
There's been a race by MJ breeders to have the highest THC strains on the market, ongoing.
The funniest strain name for me is "The Green Reefer". LOL
edgineered
(2,101 posts)Due to tests I don't partake except maybe once every couple of years. The only thing even close to today's strains were the treated thai sticks we would get in Pattaya Beach. Telling people in the 70's that after one hit you're high for hours had the same effect as telling them about the UFO's, leprechauns, and snake people!
INdemo
(6,994 posts)If anyone has an excuse to smoke it again
I live in Red State,a Red County,a Red Township
But the good news is
All my son-in-laws are Democrats...
truebluegreen
(9,033 posts)niyad
(113,552 posts)article on the evils of marijuana last week.
BeanMusical
(4,389 posts)Jesus Malverde
(10,274 posts)To schizophrenia.
Utopian Leftist
(534 posts)with cannabis.
It is because cannabis contains a very powerful anti-psychotic. It is one of the chemicals found in the CBD, if I remember correctly.
IHateTheGOP
(1,059 posts)Eleanors38
(18,318 posts)Eleanors38
(18,318 posts)Xyzse
(8,217 posts)I am not keen on inhaling smoke.
Actually not being tongue in cheek.
The family has a history of such a thing sadly.
d_r
(6,907 posts)what this article thinks they found. I think that they found that chronic MJ use was associated with less grey matter (e.g. neurons) in the OFC, and more neural connections in the OFC. That increase in neural connections in this region may be to compensate for the reduced grey matter.
From-
http://www.pnas.org/content/111/47/16913.full
Unlike the animal literature, whether exposure to marijuana leads to long-term changes in human brain structure has been equivocal. To address this limitation, we evaluated brain structural changes associated with chronic marijuana use in a large group of well-characterized marijuana users relative to age- and sex-matched nonusing controls. Our findings provide evidence that heavy, chronic marijuana users have lower OFC gray matter volumes compared with nonusing controls. This finding remained even in the smaller sample of exclusively marijuana users (n = 27, i.e., no comorbid substance use), demonstrating that this effect (i) is robust and (ii) is greater than potential effects of comorbid substance use. Similar decreases in OFC volume have been reported in marijuana using adults (29) and adolescents (12) compared with nonusing controls. Interestingly, a prospective study also found that smaller OFC volumes at 12 y of age predicted initiation of marijuana use at 16 y of age (30). These effects on the OFC are not surprising given that the OFC is a primary region in the reward network, is enriched with CB1 receptors, and is highly implicated in addictive behaviors (23, 24, 31, 32) such as those related to disruptions in motivation (33) and decision making (34, 35). Whereas others have reported alterations in various CB1-enriched regions such as the amygdala, hippocampus, ventromedial prefrontal, OFC, insula, and striatum, our findings are specific to the OFC. Several animal and human studies have demonstrated greater THC-induced down-regulation of CB1 receptors in cortical areas relative to subcortical areas, which support our findings. Given that CB1 receptors are found on excitatory terminals of cortical projection neurons, this alteration in endocannabinoid signaling could affect the plasticity of OFC circuits (36). Unfortunately, the cross-sectional nature of the present study cannot directly address whether these reductions are the cause or the consequence of marijuana use. However, neurotoxic effects of cannabis have been widely reported in the animal literature. Based on the animal literature, potential mechanisms that may lead to OFC reductions due to cannabis neurotoxicity may, therefore, include neuronal loss, changes in cell size, or a reduction in CB1 density. It is possible, however, that these OFC abnormalities may reflect preexisting pathophysiology related to vulnerability to marijuana abuse and dependence.
To determine the potential downstream effects of OFC volume reduction, we evaluated OFC functional (fcMRI) and structural connectivity (DTI). Functional connectivity analysis revealed greater connectivity within the OFC network in marijuana users compared with controls, which is concordant with existing resting-state studies (37) and task-based studies (38, 39). This increased functional connectivity in users may suggest a compensatory mechanism whereby greater network recruitment is engaged to compensate for OFC liability (40). Tomasi et al. (41) illustrated how greater functional connectivity requires higher glucose consumption (?70% of brains energy consumption), and, consequently, hubs of higher functional connectivity must be efficient. In their report, the OFC was described as having high glucose efficiency as measured by the ratio between the strength of functional integration (based on rsfMRI and the number of connections of the network nodes) and cerebral metabolic rate of glucose. Taken together, because the OFC is a network hub, observed increase in OFC functional connectivity concomitant with reductions in OFC gray matter may suggest neuroadaptive plasticity.
The findings of greater functional connectivity in OFC network in marijuana users were echoed by increased structural connectivity (i.e., FA) of the forceps minor in marijuana users relative to controls. Greater FA has been suggested to reflect better myelination and/or intact axons (42). Based on RD and AD measurements, it appears that the FA difference between the groups in the forceps minor was driven by lower RD, suggesting greater myelination in the marijuana users. Although not as widely reported, greater white matter microstructure in marijuana users has also been reported by DeLisi et al. (43) in adolescent moderate marijuana users; however, the difference from controls did not reach significance. Greater FA has also been reported in alcohol users (44, 45), which was posited to reflect a premorbid vulnerability for accelerated PFC myelin maturation in those at risk for alcohol use disorders. Among possible explanations for these findings of greater FA in marijuana users include differential effects of cannabis depending on the specific fiber tract. Specifically, because the forceps minor connects the OFC, which is enriched with CB1, it is possible that there are unique neural adaptations to the forceps minor that are unlike other white matter tracts in the brain (e.g., corpus callosum). Others have also reported antiinflammatory properties of cannabis constituents such as cannabidiol (CBD). DTI is sensitive to increased tissue water resulting in decreased FA as a result of inflammation; therefore, it is possible that any antiinflammatory effects of cannabis would lead to greater FA. Lastly, it is also possible that the effects of cannabis (i.e., CBD) may be beneficial to white matter in terms of regulation of mitochondrial activity, antioxidant processes, and modulation of clearance processes that protect neurons on the molecular level (46). Future studies are needed to examine these specific effects on white matter.
Altogether, if these effects are indeed due to neurotoxic effects of cannabis, the inverse relationship between OFC structure and connectivity suggests that OFC gray matter (vs. white matter) is more vulnerable to the effects of THC. Endogenous cannabinoids play an important role in synaptic pruning (47), therefore, introduction of exogenous cannabinoids such as THC might disrupt this system by competing for the receptors and, thereby, inhibiting synaptic pruning particularly in receptor-enriched areas such as the OFC (48). In other words, any premorbid developmental trajectory may be modified by exposure to cannabis, resulting in accelerated OFC myelin maturation. However, although the majority of the animal literature and emergent human studies illustrate the down-regulation of CB1 receptors as a result of THC, we acknowledge that longitudinal studies are needed to address causality of these neural abnormalities (49?51).
Faux pas
(14,690 posts)Utopian Leftist
(534 posts)These results will also need to be contrasted with other researcher showing that cannabinoids actually promote brain cell growth (neurogensis) even in adults.
This is what I have read elsewhere, too: that cannabis contains a chemical, which promotes neurogenesis (the creation of new brain cells).
It certainly "opens up the mind," at any rate.